The Nova system categorizes foods according to processing levels, and dietary intake instruments not developed to assess this criteria may introduce bias in epidemiological studies. To address this gap, we developed and validated the Nova Food Frequency Questionnaire (NovaFFQ) for Brazilian adults. The NovaFFQ includes commonly consumed foods and drinks based on 2017-2018 National Food Survey data. Reproducibility was assessed by comparing NovaFFQ estimates on two occasions. Criterion validity was assessed by comparing the mean dietary contribution of Nova groups obtained from the first NovaFFQ against two Nova24h. Strong reproducibility was observed with an intraclass correlation coefficient (ICC) of 0.91 for all Nova groups. Criterion validity showed a moderate ICC, ranging from 0.61 to 0.65, and substantial agreement in ranking individuals, as indicated by prevalence and bias-adjusted kappa, ranging from 0.70 to 0.74. The NovaFFQ is a valid instrument for assessing food consumption according to food processing.

The authors have declared no competing interest.

This study was funded by Coordination of Superior Level Staff Improvement (grant #88887.619685/2021-00) and the Sao Paulo Research Foundation (grant #2022/04118-5 and #2021/10993-3)

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

All procedures in this study were approved by the Research Ethics Committee of the School of Public Health of the University of Sao Paulo (approval number: #4.795.478).

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All data produced in the present study are available upon reasonable request to the authors.